An economical and sustainable alternative to established fire protection systems is fire protection by hot-dip galvanizing. In Germany, this used to require approval in individual cases (ZiE) or project-related type approval (vBG), which has now changed.
Changes in the building code
With the inclusion of DASt Guideline 027 "Determination of the component temperature of hot-dip galvanized steel components in the event of fire" in the Model Administrative Regulation Technical Building Regulations MVV TB 2023/1, fire protection by hot-dip galvanizing was declared a regulated construction method. This means that a ZiE or vBG will no longer be required in the future.
As the building law belongs to the sovereignty of the federal states, MVV TB 2023/1 still has to be implemented by the individual federal states in order to become valid there. This has already been done for Brandenburg, Bremen and Mecklenburg-Western Pomerania, and experience shows that MVV TB 2023/1 can be expected to be implemented in the other federal states in the next few months. An up-to-date overview of the implementation status of MVV TB 2023/1 is provided by Deutsches Institut für Bautechnik (DIBt) as the highest technical construction authority.
Hot-dip galvanizing as a fire protection system
The fire resistance of steel structures is improved by hot-dip galvanizing, since hot-dip galvanized steels are characterized by lower emissivity. Emissivity is a measure of how much a material exchanges thermal radiation with its surroundings. Particularly in the initial phase of a fire, reduced emissivity values result in significantly delayed heating of the steel components and can make a significant contribution to achieving the required fire resistance of R30, especially in the case of components with sufficient solidity.
The range of applications for fire protection by hot-dip galvanizing in steel construction includes hall buildings, residential and commercial buildings, individual columns, pergola structures and industrial elevations. Hot-dip galvanized steel is also a sustainable, circular material and also plays a significant role in energy transformation, including the expansion of power grids and the development of wind and solar energy.
Anyone wishing to use hot-dip galvanizing as fire protection must provide mathematical proof by means of a hot design. The Institut Feuerverzinken offers a free design tool for this purpose. In addition, software manufacturers such as mb AEC Software and Dlubal Software have design programs for fire protection by hot-dip galvanizing in their portfolios.
